Prince William and Kate Middleton secretly visited an NHS call centre to boost the morale of its employees in London on Thursday. They are the first royals to undertake a visit to frontline health workers amid the coronavirus pandemic that has spread throughout the globe.

The Duke and Duchess of Cambridge visited NHS 111 call centre to highlight its vital work to manage the coronavirus outbreak. The royal couple was seen following hygiene guidelines as they used hand sanitisers twice and consciously didn't shake hands with anyone, Hello reports.

Supervisor Courtney Campbell, 32, briefly forgot the rules and reached out to shake their hands. Prince William laughed: "Don't shake hands!" But he was ready to do a photo op if they were all "not within a metre of each other."

Kate Middleton was dressed in a pink trouser-suit from Marks & Spencer. Her look was understated in a white blouse, muted heels, natural makeup and hair styled in her famous blow-dry. William meanwhile donned black suit and trouser combo.

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‘Catherine and I were proud to visit staff working at NHS 111, to pass on our personal thanks, along with those of my grandmother and father, to staff working around the clock to provide care and advice to those that need it most.’ - The Duke of Cambridge . @kensingtonroyal yesterday visited the London Ambulance Service in Croydon, where they thanked NHS 111 call handlers and staff for the vital work they are doing. #NHSThankYou Before contacting NHS 111, you can alleviate pressure on the system by visiting nhs.uk/coronavirus. . Photos ©️ Kensington Palace

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The 37-year-old prince praised the health service and thanked the staff on behalf of the British royal family. William urged the public to stay and home and non-essential travel.

"That is why Catherine and I were proud to visit staff working at NHS 111, to pass on our personal thanks, along with those of my grandmother and father, to staff working around the clock to provide care and advice to those that need it most. It was also brilliant to see the great online tools for those with mild symptoms or worries," the father-of-three said.

"Not only are NHS staff and emergency workers responding to the needs of the public, they – like the rest of us – are concerned about their families, friends and loved ones. They need our support as much as we need theirs," he added.

William said: "All of us have a part to play if we're going to protect the most vulnerable. That means acting on the latest expert advice, staying home if we or those we live with have symptoms, and avoiding non-essential contact to help reduce the spread of the virus."

Tracy Pidgeon, 54, a manager currently helping with calls, said the Duke seemed to be nostalgic for his old job as a pilot for East Anglian Air Ambulance. The Duke of Cambridge met call handler Paula White, a former telephonist at Buckingham Palace who had met him when he was a baby.

"Was I behaving myself? A rowdy little child?" joked William. She said later: "I said, 'I can't say sir – the press are here!'" White recalling her former job and said she worked at the palace when Princess Diana was getting married. She added that princess Diana used to visit the switchboard room when William was a baby.

About William and Kate's visit she said: "It's lovely. It's like a pat on the back. It just raises morale."

Calls to 111 calls to the centre has nearly quadrupled since the crisis began, from around 7,000 to 25,000 a day across London alone. Dr Agatha Nortley-Meshe, a GP and the assistant medical director of LAS, said the team was working "extremely hard."

Royal Tour of Ireland
Ireland's interim Prime Minister Leo Varadkar (second left) with Prince William and their respective partners, Matthew Barrett and and Catherine, Duchess of Cambridge at the Government Buildings in Dublin on Tuesday Photo: AFP / PAUL FAITH

He added that for future visits if social distancing is still applicable, remote conferencing may be considered. He further added that people should only call 999 if they have "a very serious, potentially life-threatening emergency" otherwise, "call 111 if you cannot get the advice you need from NHS online."